Segmented mechanical shafting alignment tool and method

ABSTRACT

A tool and method for aligning multiple shaft segments which are coupled together to form a single rotating shaft. The device comprises a cylindrical bar having an annular, axially-extending outer surface, rotating means on a first end of the bar, and engaging/disengaging means fixed on the second end of the bar. The bar is temporarily inserted through a bolt hole in the collar of the first shaft and partially through an aligned hole in an adjacent coupling of the second shaft until at least a portion of the engaging/disengaging means is positioned within the bolt hole of the second collar. The engaging/disengaging means engages the second collar so that a turning force from the first shaft is transmitted to the second shaft. The engaging/disengaging means also disengages from the second collar by rotating the bar after rotation of the shaft is ceased.

This application is a continuation of application Ser. No. 08/880,237filed Jun. 23, 1997 now U.S. Pat. No. 5,920,999 which claims the benefitof U.S. Provisional Application No. 60/029,907 filed Oct. 31, 1996, andU.S. Provisional Application No. 60/021,091 filed Jul. 2, 1996.

FIELD OF THE INVENTION

The present invention relates to a tool for aligning segmentedmechanical shafting, such as steam turbines, duringinitial-installation, coupling alignment checks and other maintenancework.

BACKGROUND OF THE INVENTION

The typical steam turbine-generator consists of multiple shaft segmentshaving coupling collars which are coupled together to form a singlerotating shaft. During turbine outages, maintenance personnel uncoupleand remove one or more shaft segments for inspection. After uncouplingand prior to removal, the alignment of each turbine shaft segment ismeasured. During reassembly, the alignment between couplings is onceagain measured and compared to the original measurement ormanufacturer's specifications to ensure that the shaft will be properlyaligned. If alignment corrections are necessary, additional alignmentmeasurements follow after each correction is made.

Shaft alignment measurements, more familiarly referred to as "couplingalignment checks", are a standardized sequence of rotational stepsmeasuring the parallel and angular misalignment between two couplings.These steps include: temporarily connecting a pair of adjacent shaftsegments; turning the pair of shaft segments several times to removesag; rotating the shaft segments in 90 degree intervals; stopping aftereach interval to take a reading; and repeating the 90 turning processuntil a minimum of two full rotations is achieved. In total, for onealignment check, a minimum of 8 starts and stops is required to completetwo rotations of the shafts.

Each shaft segment is very large and may weight up to 320,000 pounds. Inorder to connect and rotate the large shafts, barstock is insertedthrough aligned bolt holes of adjacent couplings and a turning force isapplied by, for example, an overhead crane. The barstock temporarilyconnects the couplings during the rotation phase so that the turningforce applied to one shaft segment is transmitted to the adjacent shaftsegment. After each 90 degree rotation, the shaft segments must bedisconnected to conduct an alignment check.

To disconnect the shaft segments, rotation is stopped and the barstockremoved. Since the shafts are extremely heavy, the barstock typicallybinds in the bolt holes due to distortion (bending) of the barstockduring rotation. Removing the barstock to make an alignment check isinhibited since this "torqued" condition remains in the bent barstockeven when the turning force is removed. In order to relieve this"torqued" condition, the barstock must be loosened within the clearanceof its hole. Loosening the barstock is extremely difficult and requiresthat one of the shaft segments be rotated in a reverse directionrelative to the other.

Currently, several methods exist for applying the turning force requiredduring coupling alignment checks. The most commonly used method is thecombined use of a crane, a lifting cable, and round pin. The round pinis inserted halfway into one of the empty coupling bolt holes and thecrane cable is looped over the free end of the round pin. The shaft orshaft(s) are then rotated a small amount by pulling the pin upward withthe crane. Full rotation is achieved by relocating the pin in differentbolt holes around the circumference of the shaft collar and pulling withthe crane. This process is normally used for turning one shaftindividually or, when used in conjunction with the aforementionedbarstock connection, can be used to turn two shafts at the same time.However, as more shaft units are connected using barstock and turned inthis manner, the load capacity of a single crane is challenged. As aresult, a second pin and overhead crane must be used in conjunction withthe first. This situation is undesirable since a complete alignmentcheck may typically take up to 8 hours to perform, during which time twomaintenance cranes are occupied.

As an alternative to using maintenance cranes, the already existingmanufacturer-supplied turning gear may be used to provide the necessaryturning force. The turning gear consists of a motor, speed reducer, anda large drive gear permanently attached to one of the shafts. Duringcoupling checks, when barstock is inserted into any unbolted couplings,the turning gear will drive all the shaft segments at a very slow speed.Using the turning gear eliminates the need to use maintenance cranes;however, the turning gear does not alleviate the barstock bindingproblems described above.

Therefore, it would be desirable to provide an alignment tool which isconstructed to temporarily connect, and quickly and easily disconnectadjacent shaft segments without becoming bound in the coupling boltholes.

With the recent introduction of laser alignment technology, it hasbecame absolutely necessary to maintain the clock position of the twocouplings halves within seconds of arc. The barstock connection methodcannot maintain the tight clocking relationship required of lasers dueto the angular slippage between the couplings which occurs due tobarstock bending.

Therefore, it would also be desirable to provide an alignment tool whichmaintains the relative angular position between the two shaft segmentsduring the rotation phase of an alignment check.

When the large shaft segments are bolted together during initialassembly, it is often found that the axes of the shaft segments are notconcentric. If the axes are not concentric, one shaft segment will"wobble" in relationship to the other during rotation causing turbineshaft vibration. To minimize turbine shaft vibration, the couplingcollars should be bolted together as concentric as possible. This task,however, is not easy due to the extreme weight and size of each shaftsegment.

In the prior art, adjusting coupling collar concentricity usuallyrequires numerous hours of trial and error adjustments to the concentric(axial) alignment by loosening the connection bolts, hydraulicallyjacking one shaft segment relative to another, and then tightening theconnection bolts. This is an inefficient and strenuous technique.

Another known method of correcting coupling concentricity involvesjacking screw arrangements made to fit on the periphery of the couplingcollars. While this technique is more efficient than the trial-by-errortechnique described above, it is also strenuous and time consuming, andrequires expensive and bulky specialized tooling.

Therefore it would be desirable to provide an alignment tool which jacksone shaft segment relative to the other to achieve coupling collarconcentricity in the shaft.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an alignment toolwhich is constructed to temporarily connect together two adjacent shaftsegments during coupling alignment rotation, and which is constructed toquickly disconnect the shaft segments after each rotation phase of thecoupling alignment check.

It is a further object of the present invention to provide an alignmenttool which maintains the relative angular position constant between thetwo shaft segments during the rotation phase of an alignment check sothat shaft alignment data can be collected using laser alignmentequipment.

It is an additional object of the present invention to provide analignment tool which may be employed simultaneously at each couplinglocation on a turbine shaft.

It is a further object of the present invention to provide an alignmenttool constructed to adjust the coupling collar concentricity of adjacentshaft segments during assembly.

These and other objects are accomplished by providing an inventivecoupling pin device and method of using it which allows two or morein-line shafts to be temporarily coupled together and rotated as a unit.In addition, the device also allows the same shafts to be quicklydisconnected, with no residual turning stress, after turning is ceased.

The tool for aligning multiple shaft segments comprises a two-piece pinassembly which is temporarily inserted through aligned bolt holes in thecouplings of the adjacent shaft segments. The pin assembly comprises apair of elongate, cylindrical bars. Each bar has an annular, axiallyextending outer surface, first and second end surfaces, a notch formedin the first end of the bar, and means on the second end of the bar forrotating the bar. The notches are constructed and arranged tocooperatively engage with one another so that a turning force from onebar is transmitted to the other bar. The notches are also constructedand arranged to disengage from one another when the bars are rotated.

The notches have an axial notch surface extending axially a distance "Y"along a plane defined by a chord on the first end surface. The chord isshorter than the diameter of the bar.

The notches also have a radial notch surface extending radiallyoutwardly a distance "X" from the axial inner end of the axial notchsurface. The distance "X" is greater than the radius of the bar whenmeasured along a line extending perpendicular to the axial notch surfacefrom the midpoint of the chord to the outer surface of the bar.Preferably, the distance "X" is equal to about 1/2 of the bar diameterplus 1/16 inch.

The bars are constructed and arranged to disengage when the bars arerotated 90 degrees from an engaged position.

The rotating means comprises a lug fixed to the second end surface ofthe bar. The lug has multiple flat surfaces which are constructed andarranged to receive a wrench or socket for applying a turning force. Thelug may have a square, hexagonal or twelve-point shape. The rotatingmeans may also comprise recessed hex socket or pin hole sockets whichcooperate with a hex or pin wrench. The rotating means may also includea linear notch indicator for indicating the angular orientation of thenotch.

The pin assembly preferably includes a sleeve fixed to the outer surfaceof the bars proximate the notch. The sleeve is shorter than the axialdistance from the notch to the rotating means.

The pin assembly may include adjustable extensions fixed to andextending perpendicular from the axial notch surface on one of the bars.The extensions may comprise set screws extending from threaded bores inthe axial notch surface, or the extensions may comprise shims removablysecured to the axial notch surface.

The pin assembly may also include a second sleeve fixed to the outersurface of the first sleeve proximate the rotating means. Preferably,the second sleeve has a frusto-conical outer surface profile.

In another embodiment of the invention, a coupling runout eliminator(CRE) pin assembly comprises a pair of elongate, cylindrical bars. Eachbar comprises an annular, axially-extending outer surface, first andsecond end surfaces, and a notch formed in the first end of the bar. Thenotch is defined by a radial notch surface and a fully or partiallytapered, axial notch surface.

The pin assembly includes means on the second end of at least one barfor rotating the bar and means for temporarily connecting the bars withthe tapered, axial notch surfaces overlapping, and means for adjustingthe axial location of overlap of the notch surfaces by axially movingthe bars relative to one another.

The bars are constructed and arranged to cooperatively engage withoverlapping tapered surfaces and jack one shaft segment relative to anadjacent shaft segment when the axial location of overlap of the notchesis adjusted.

The axial notch surface is preferably a full or partially inclined planeextending axially and radially outwardly. The plane is defined by achord on the first end surface. The chord is shorter than the diameterof the bar.

The radial notch surface extends radially outwardly from the inner endof the axial notch surface to the outer annular outer surface. Theradial notch surface extends radially outwardly a distance "X" from theaxial inner end of the axial notch surface. On the bar having thepartially-tapered, axial notch surface, the axial notch surfacecomprises a flat plane portion extending parallel to the longitudinalaxis of said bar and an inclined portion extending axially and radiallyoutwardly from the flat plane portion. The distance "X" is greater thanthe radius of the bar when measured along a line extendingperpendicularly from the flat plane portion to the outer annular surfaceof the bar. Preferably, the distance "X" is equal to the radius of thebar plus 1/4-5/16 inches. On the bar having the fully-tapered, axialnotch surface, the distance "X" is less than the radius of the bar whenmeasured along a line extending perpendicularly from the axial notchsurface to the outer annular surface of the bar.

The temporary connecting means comprises a cylindrical bore extendingthrough one bar from the radial notch surface to the other end surface,a cylindrical threaded bore in the other bar extending from the firstend surface longitudinally to a point intermediate the bar, and a boltextending through the cylindrical bore and into the threaded bore.

The pin assembly may include a linear notch indicator on the rotatingmeans for indicating the angular orientation of the notch.

The pin assembly also includes a sleeve fixed to the outer surface ofthe bars proximate the notch. The sleeve is shorter than the axialdistance from the notch to the rotating means.

The pin assembly may also include adjustable extensions fixed to andextending perpendicularly from the axial notch surface of one of thebars. The extensions may comprise shims removably secured to the axialnotch surface.

In a further embodiment, one bar has a notch formed in the first end ofthe bar and the other bar has a tab formed in the first end of the bar.The tab and notch are constructed and arranged to cooperatively engageso that a turning force from one bar is transmitted to the other bar.The tab and notch are also constructed and arranged to disengage fromone another so that the shaft segments can rotate independent of the oneanother. In this embodiment, the tab and notch are constructed to engagewhen one shaft segment is rotated in either the clockwise orcounterclockwise direction.

In an additional embodiment, the pin assembly comprises two elongatecylindrical bars. The first elongate, cylindrical bar has an annular,axially extending outer surface; means on one end of the bar forrotating the bar within one of the aligned apertures; and means on theother end of the bar for engaging with and disengaging from the secondbar.

The second elongate, cylindrical bar has an annular, axially extendingouter surface; means on one end of the bar for engaging with anddisengaging from the first bar; and a threaded, annular,axially-extending internal bore. The engagement means is constructed andarranged so that a rotational force is transmitted from one bar to theother bar. The disengagement means is constructed and arranged so thatthe bars are disengaged when the bars are rotated 90 degrees from anengaged position.

The present invention also provides a method of aligning multiple shaftsegments which are coupled together to form a single rotating shaft. Themethod comprises the steps of first inserting a two-piece pin assemblythrough aligned apertures in the couplings of adjacent shaft segments.The pin assembly may be of the type described above. Next, the couplingsare temporarily connected by orienting the pin assemblies such that thenotch faces are in contact with one another and the couplings rotatetogether as a unit.

The shaft segments are then rotated to remove sag in the shaft segments.Then, the couplings are disengaged by rotating the pin assemblies 90degrees within the bolt holes. After the couplings are disengaged, thecoupling alignment is measured. Preferably, the pin assemblies arerotated by applying a torquing tool to the rotating means.

The present invention also provides a method of adjusting the clockposition of the couplings by adjusting the distance between theoverlapping axial notch surfaces by providing adjustable extensionsfixed to and extending perpendicular to the axial notch surface on oneof the bars.

The present invention also provides a method of correcting couplingcollar concentricity of multiple shaft segments which are coupledtogether to form a single rotating shaft. The method comprises the stepsof first disconnecting the shaft segments and inserting temporary bolts(bolts with sufficient clearance to make adjustments) into spaced bolthole locations in the couplings and slightly tightening the temporarybolts. The clock position of the couplings can then be aligned as neededby installing and adjusting two CRE pin assemblies (described above) inadjacent bolt holes. After the clock position of the couplings isaligned, the temporary bolts are firmly tightened and the two CRE pinassemblies are removed.

Next, the position of maximum positive differential coupling runout(DCR) is located and marked. A CRE pin assembly is inserted at thelocation of maximum DCR and at locations 90 degrees from that position.The temporary bolts are then loosened. The measured DCR is corrected byadjusting the CRE pin assemblies.

The step of aligning the clock position includes the steps of orientingthe axial notch faces of the CRE pin assemblies such that the length ofthe notch corner is parallel to a radial line extending from the centerof the coupling through the center of the bolt hole in which the CRE pinassemblies is installed, and rotating the adjustment means on each CREpin assembly.

The step of inserting a CRE pin assembly at the location of maximum DCRand at locations 90 degrees from that position includes orienting theCRE pin assemblies such that the length of the notch corner isperpendicular to a radial line extending from the center of the couplingthrough the center of the bolt hole in which the CRE pin assembly isinstalled.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a pin assembly according to anembodiment of the invention;

FIG. 2 is an end view taken along line 2--2 of FIG. 1;

FIG. 3 is an end view taken along line 3--3 of FIG. 1;

FIG. 4 is a side elevational view of two standard flat flanged typecouplings (shown in cross section) connected during rotation by the pinassembly of an embodiment of the invention;

FIG. 5 is a side elevational view of two recessed bolt circle typecouplings (shown in cross section) connected during rotation by the pinassembly of an embodiment of the invention;

FIG. 6 is an enlarged, side elevational view of a pin assembly in theengaged position during rotation of two couplings (shown in crosssection);

FIG. 7 is a side elevational view of two standard flat flanged typecouplings (shown in cross section) disconnected by the pin assembly ofan embodiment of the invention;

FIG. 8 is a side elevational view of two recessed bolt circle typecouplings (shown in cross section) disconnected by the pin assembly ofan embodiment of the invention;

FIG. 9 is an enlarged, (shown in cross section) view of a pin assemblyin the disengaged position during an alignment measurement of twocouplings (shown in cross section);

FIG. 10 is a side elevational view of a further embodiment of theinvention showing a pin assembly in the engaged position during rotationof two couplings (shown in cross section) by a crane cable (shown inphantom);

FIG. 11 is a side elevational view of another embodiment of theinvention connecting two couplings (shown in cross section) includingadjustment screws;

FIG. 12 is a sectional view taken along line 12--12 of FIG. 11;

FIG. 13 is a side elevational view of a further embodiment the inventionconnecting two couplings (shown in cross section) adjustment shims;

FIG. 14 is a sectional view taken along line 14--14 of FIG. 13;

FIG. 15 is a side elevational view of the first half of a pin assemblyof an additional embodiment of the invention;

FIG. 16 is a side elevational view of the second half of a pin assemblyof an additional embodiment of the invention;

FIG. 16a is an enlarged, sectional, side elevational view of the notchsurface of the bar shown in FIG. 16;

FIG. 17 is a side elevational view of two recessed bolt circle typecouplings (shown in cross section) connected by the pin assembly ofFIGS. 15 and 16;

FIG. 18 is a side elevational view of two recessed bolt circle typecouplings connected by a pin assembly of yet a further embodiment of theinvention;

FIG. 19 is a cross-sectional view taken along line 19--19 of FIG. 18;

FIG. 20 is a side elevational view of two recessed bolt circle typecouplings (shown in cross section) disconnected by the pin assembly ofFIG. 18;

FIG. 21 is a cross-sectional view taken along line 21--21 of FIG. 20;

FIG. 22 is a side elevational view of two couplings (shown in crosssection) connected by a pin assembly of an additional embodiment of theinvention;

FIG. 23 is a cross-sectional view taken along line 23--23 of FIG. 22;

FIG. 24 is a schematic illustration of the differential coupling runoutof two couplings which is corrected in accordance with a method of thepresent invention;

FIG. 25 is an enlarged, sectional view of FIG. 24 showing the angularlocation and orientation of two pin assemblies used in accordance with amethod of the present invention; and

FIG. 26 is a schematic illustration of the location of pin assembliesused in accordance with a method of the present invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

For the purpose of illustration, preferred embodiments of the claimedinvention are shown in FIGS. 1-26 wherein like numerals are used todesignate like parts throughout the drawings.

In a first embodiment of the invention, the coupling pin devicecomprises a pair of cooperating pin assemblies 12 which are insertedthrough aligned bolt holes of adjacent coupling collars. One pinassembly 12 is shown in FIGS. 1-3. The pin assembly 12 comprises a steelbar 14 and a bronze, brass, or other soft metal sleeve 16 heated andshrunk fit over the annular, axially extending outer surface 14a of thebar 14 so as to join the bar 14 and sleeve 16 together.

The bar 14 has two end surfaces 14b, 14c. A notch, designated generallyas reference numeral 15, is formed in the notch end 14b of the bar 14.The notch. 15 is defined by an axial notch surface 15a and a radialnotch surface 15b.

Referring to FIGS. 1 and 2, the axial notch surface 15a is formed,preferably by machining, longitudinally into the bar from the notch endsurface 14b of the bar 14. The axial notch surface 15a extendslongitudinally a distance "Y", preferably about 1 inch nominal, andforms a planar surface parallel to the longitudinal axis 14e of the bar14.

The radial notch surface 15b is formed, preferably by machining,radially into the bar from the outer annular surface 14a of the bar 14and intersects the axial notch surface 15a, thereby forming the notch15. The radial notch surface extends radially a distance "X" from theaxial notch surface 15a to the outer surface 14a. The radial notchsurface extends transversely, and preferably perpendicularly, to theaxial notch surface 15a and the longitudinal axis 14e of the bar 14. Thedistance "X" must be greater than the radius "R" of the bar, and ispreferably equal to the radius of the bar 14 plus an additionalone-sixteenth of an inch nominal.

Nominal dimensions are given to illustrate general sizing of the notch15. The most critical dimension of the notch 15 is the dimension "X",which must be greater than the radius of the bar 14, and is preferablyequal to the radius "R" of the bar plus one-sixteenth of an inchnominal. This locates the corner 14d of the notch above the longitudinalaxis 14e. The corner 14d is also machined to a one-sixteenth of an inchnominal radius. As shown later in FIGS. 7, 8, and 9, the geometry of thenotch 15 enables the pin assemblies 12 to disconnect from one anotherunder load when rotated 90 degrees.

The notch end 14b of the bar 14 is shown in detail in FIG. 2 wherein theaxial notch surface 15a is projected as a line which subtends thecircumference of the annular outer surface 14a of the bar 14 nominallyabout one-sixteenth of an inch above the bar diameter 14e. The notch endsurface 14b is smaller than a full semi-circle of the bar, and comprisesa shape bounded by the outer edge of the axial notch surface 15a and anarc of the outer annular surface 14a of the bar 14.

A drive head 17 is formed, preferably by machining, on the drive end 14cof the bar 14 so that the bar 14 can be rotated with a standard wrench(not shown). Referring to FIGS. 1 and 3, the drive head 17 is depictedas a hex head in a preferred embodiment, but may be a square-end head,twelve-point head, or any other geometric shape head which facilitateseasy turning by a standard wrench, socket wrench, or other torquingtool.

A notch locator slot 18 is formed in the end surface 17a of the hexdrive 17. The notch locator slot 18 preferably comprises a linear groovemachined parallel to the axial notch surface 15a. The notch locator slot18 is used as an easy reference to determine the angular orientation ofthe axial notch surface 15a. To also aid referencing the angularorientation of the axial notch surface 15a and the notch end surface14b, paint 18a may be applied to one half of the drive head end surface17a corresponding to the notch end surface.

Referring to FIG. 3, the notch locator slot 18 is shown traversing thehexagonal-shaped drive head 17. Paint 18a (illustrated by crosshatching) is applied to one half of the drive head end surface 17a tohelp indicate the angular orientation of the axial notch surface 15a andnotch end surface 14b.

A pair of pin assemblies 12 are shown in cooperating engagement with oneanother to connect during rotation two standard flat flange typecouplings 21a and 21b in FIG. 4, and two recessed bolt circle typecouplings 31a and 31b in FIG. 5. As seen in greater detail in FIG. 6,the connection is provided by inserting one pin assembly into each of apair of aligned, opposed coupling bolt holes 25a, 25b until the notches15 overlap. As the first coupling 21a is rotated in the "Y" directionshown in FIG. 6, the notch from the pin assembly 12a in the firstcoupling 21a contacts the notch on the second pin assembly 12b, therebycausing the couplings 21a and 21b to rotate together as a unit.

A pair of pin assemblies 12 are shown disengaged, for example at the endof the rotation phase of a coupling alignment check, on two standardflat flange type couplings 21a and 21b in FIG. 7, and two recessed boltcircle type couplings 31a and 31b in FIG. 8. As seen in greater detailin FIG. 9, the couplings are disconnected by rotating each pin assembly90 degrees within the bolt holes 25a, 25b, thereby causing thepreviously engaged axial notch surfaces 15a to be separated by adisengagement gap 23 and change their angular orientation relative tothe direction of rotation of the couplings. In FIG. 9, the direction ofrotation of the couplings is in the "Z" direction or perpendicular tothe plane of the drawing sheet.

The pin assemblies 12 are rotated by applying a wrench or other torquingtool to the drive head 17 and simultaneously rotating both pinassemblies 90 degrees. The pin assemblies may be turned either clockwiseor counterclockwise so long as both pins are turned in the samedirection. The pin assemblies 12 can be turned very easily since turningresistance is minimal due to the slip fit of the bronze sleeve 16 andthe bolt hole 25 inner surface which act together like a shaft and abearing.

The disengagement notch gap 23 results from the fact that the depth "X"of the radial notch surfaces 15b (shown in FIGS. 1 and 2) of each of themating pins assemblies is greater than the bar radius "R", preferablyequal to the bar radius "R" plus one-sixteenth of an inch nominal, andbecause the coupling bolt holes have bolt circles diameters that arenearly concentric.

In a second embodiment of the invention, the coupling pin devicecomprises a pair of cooperating pin assemblies 112 as illustrated inFIG. 10. The pin assemblies 112a and 112b have the same construction asthe pin assemblies 12a and 12b of the first embodiment except that onepin assembly 112a is longer than the mating pin assembly 112b andincludes a second sleeve 29 which is constructed to slide over the driveend 114 of the first sleeve 116 of the long pin assembly 112a. Thesecond sleeve 29 has an annular outer surface which is tapered along thelength of the sleeve 29 thereby forming a frusto-conical outer surfaceprofile.

In this embodiment, the extra length of the long pin assembly 112aprojects beyond the back face 21c of the coupling 21a, thereby providinga connection point for a crane cable 28 to be looped over the drive end114c of the long pin assembly 112a. The second sleeve 29 is constructedto slide over the extended end of the long pin assembly 112a with thesmaller, tapered end abutting the back face 21c of the coupling 21a. Acrane cable 28 may be looped over the sleeve 29 and pulled upwardly toapply a turning force to the couplings. The couplings 21a and 21b willthen rotate in the direction shown in FIG. 10.

A third embodiment of the coupling pin device of the present inventioncomprises a pair of cooperating pin assemblies 212 as illustrated inFIGS. 11 and 12. The pin assemblies 212a and 212b have the sameconstruction as the pin assemblies 12 of the first embodiment except apair of adjustment screws 42 are fixed to and protrude from the axialnotch surface 215a of one of the pin assemblies 212a. Referring to FIG.12, two adjustment screws 42 are screwed into threaded bores in theaxial notch surface 215a of one of the pin assemblies 212a. A portion42a of the adjustment screws 42 protrudes from the axial notch surface215a and contacts the other axial notch surface 215b during rotation.

The adjustment screws 42 can be adjusted to change the length of theextension portion 42a of the screws 42 which protrudes from the axialnotch surface 215a. As a result, the centerlines 44a and 46a of themating bolt holes 44 and 46 will also be adjusted to the desired angularpositions allowing bolting to be installed easier. Further, the angularposition between the first pin assembly 212a and the mating pin 212b isadjusted by extension or retraction of the adjustment set screws 42.

A fourth embodiment of the coupling pin device of the present inventioncomprises a pair of cooperating pin assemblies 312a, 312b as illustratedin FIGS. 13 and 14. The pin assemblies 312a and 312b have the sameconstruction as the pin assemblies 12 of the first embodiment exceptthat one of the pin assemblies 312a includes a primary metal shim 52with countersunk through holes, and secondary, thinner shims 54 behindthe primary shim 52. The shims 52, 54 are attached to the axial notchsurface 315a of one of the pin assemblies 312a. The shims 52, 54protrude from the axial notch surface 315a of one pin assembly andcontact the other notch surface 315b during rotation.

Referring to FIG. 14, the shims 52, 54 are attached to the axial notchsurface by two flat head screws 56 which are screwed into threaded boresin the axial notch surface 315a. The distance which the primary shimprotrudes can be adjusted by removing the flat head screws 56 and addingor subtracting the number of secondary shims 54 behind the primary shim52. As a result, the centerline 44a and 46a of the mating bolt holes 44and 46 will be adjusted to the desired angular position in the samemanner as the embodiment described above with reference to FIGS. 11 and12.

A fifth embodiment of the coupling pin device of the present inventioncomprises a pair of cooperating pin assemblies 412 and 413 asillustrated in FIGS. 15-17. The pin assemblies 412 and 413 of thisembodiment are constructed to "scissor" one shaft segment relative toanother to adjust coupling collar concentricity or "coupling runout".

Each CRE pin assembly 412, 413 comprises of a steel bar 414 and abronze, brass, or other soft metal sleeve 416 heated and shrunk fit overthe annular, axially extending outer surface of the bar 414 so as tojoin the bar 414 and sleeve 416 together. Each bar 414 has a notch endsurface 414b in which a notch is formed. The notch is defined by anaxial notch surface and a radial notch surface.

Referring to FIG. 15, the tapered axial notch surface 412a of the firstpin assembly 412 is formed, preferably by machining, longitudinally intothe bar from the notch end surface 414b of the bar 414. The axial notchsurface 412a extends longitudinally a distance "Y", preferably about 2inches nominal, and radially outwardly at an angle theta e relative tothe longitudinal axis 414e of the bar 414. Preferably, the angle theta Θis about 2 degrees.

The radial notch surface 412b of the first pin assembly 412 is formed,preferably by machining, radially into the bar from the outer annularsurface and intersects the tapered, axial notch surface 412a, therebyforming the notch. The radial notch surface extends radially a distance"X" from the axial notch surface 412a to the outer annular surface. Theradial notch surface extends in a direction transverse to the axialsurface 412a and the longitudinal axis 414e of the bar 414. The distance"X" is preferably less than the radius "R" of the bar, and is preferablyequal to the radius of the bar 414 minus 9/32 inches.

Referring to FIGS. 16 and 16a, the axial notch surface of the second pinassembly 413 comprises the combination of the flat axial notch surface413a on the inner side of the notch and the relatively short outertapered surface 413c. Both surfaces 413a and 413c are formed, preferablyby machining, longitudinally into the bar from the notch end surface414b of the bar 414. The inward axial notch surface 413a extendslongitudinally a distance "Y", preferably about 115/16 inches nominal.The outer, tapered axial notch surface 413c extends longitudinally adistance "Z", preferably about 1/16 inches nominal, and radiallyoutwardly at an angle theta Θ relative to the longitudinal axis 414e.Preferably, the angle theta Θ is about 2 degrees.

The radial notch surface 413b of the second pin assembly 413 is formed,preferably by machining, radially into the bar from the outer annularsurface 414a and intersects the inner axial notch surface 413a, therebyforming the notch. The radial notch surface extends radially a distance"X" from the axial notch surface 413a to the outer annular surface. Theradial notch surface 413b extends in a direction transverse to the inneraxial surface 413a and the longitudinal axis of the bar 414e.

The distance "X" is preferably greater than the radius "R" of the bar,and is preferably equal to the radius of the bar 414 plus 1/4-5/16inches.

The first CRE pin assembly 412 has a drive head 417 formed, preferablyby machining, on the other end 414c of the bar 414 so that thecooperating pin assemblies 412, 413 can be rotated with a standardwrench (not shown). Referring to FIG. 15 and 17, the drive head 417 isdepicted as a hex head in a preferred embodiment, but may be asquare-end head, twelve-point head, or any other geometric shape headwhich facilitates easy turning via a standard wrench, socket wrench, orother torquing tool.

A notch locator slot 418 is formed in the end surface of the hex drive417. The notch locator slot 418 preferably comprises a linear groovemachined generally parallel to the axial notch surface 412a. The notchlocator slot 418 is used as an easy reference to determine the angularorientation of the axial notch surface 412a. To also aid referencing theangular orientation of the axial notch surface 412a, paint may beapplied to one half of the drive head end surface.

The first CRE pin assembly 412 further includes a threaded bore 420extending longitudinally into the bar 414 from the radial notch surface412b. The threaded bore 420 is designed to receive the threaded end 422bof a bolt 422, shown in FIG. 16, to temporarily connect the pinassemblies 412 and 413 with axial notch surfaces overlapping. Thethreaded bore 420 is preferably about 2 inches long and extendsgenerally parallel to the longitudinal axis 414e of the bar 414 of thefirst pin assembly 412.

The second CRE pin assembly 413 includes a longitudinal bore and athreaded rod or bolt 422 inserted therethrough for temporarilyconnecting the pin assemblies 412 and 413. The bolt 422 has fine threads422b on one end and a head 422a on the other. In FIG. 16, the head 422ais depicted as a hex head in a preferred embodiment, but may be asquare-end head, twelve-point head, or any other geometric shape headwhich facilitates easy turning via a standard wrench, socket wrench, orother torquing tool.

The second CRE pin assembly 413 also has two holes 414f on end 414c toturn the bar of the second pin assembly 413. The drive holes 414f areformed, preferably by machining, on the drive end 414c of the bar 414 sothat the bar can be rotated with a pin wrench (not shown).

A pair of CRE pin assemblies 412, 413 are shown in FIG. 17 incooperating engagement with one another to correct the couplingconcentricity of two standard flat flanged type couplings 431a and 431b.The connection between the two CRE pin assemblies 412, 413 is providedby inserting one pin assembly into each of a pair of aligned, opposedcoupling bolt holes until the notches overlap. Then, the threaded bolt422 is inserted through the bore in the second pin assembly 412b andscrewed into the threaded bore of the first pin assembly 412a.

Once the CRE pin assemblies are connected, one coupling can be"scissored" relative to the other by adjusting the axial location ofoverlap of the notches. The axial location of overlap is adjusted byapplying a turning force to the bolt head 422a which causes the bars tomove axially relative to one another due to the bolt/threaded boreconnection, and causing the bars to move radially relative to oneanother due to the tapered axial notch surface 412a. Using the pinassembly of the present invention, the coupling concentricity of theadjacent couplings can be precisely adjusted.

Referring to FIG. 16a, the pin assembly 413 may be include a metal shim452 added to the axial notch surface 413a similar to the fourthembodiment. The shim 452 may be fixed to the axial notch surface 413apreferably by adhesive tape or by two flat head screws which are screwedinto threaded bores in the axial notch surface 413a.

A sixth embodiment of the coupling pin device of the present inventioncomprises a pair of cooperating pin assemblies 512a and 512b asillustrated in FIGS. 18-21. Each pin assembly 512 comprises a steel bar514 and a bronze, brass, or other soft metal sleeve 516 heated andshrunk fit over the annular, axially extending outer surface 514a of thebar 514 so as to join the bar 514 and sleeve 516 together.

Similar to the pin assemblies described above with reference to FIGS.1-9, each bar 514 has a drive head 517 formed, preferably by machining,in the drive end 514c of the bar 514 so that the bar 514 can be rotatedwith a standard wrench (not shown). Referring to FIGS. 18 and 20, thedrive head 517 is depicted as a hex head in a preferred embodiment, butmay be a square-end head, twelve-point head, or any other geometricshape head which facilitates easy turning via a standard wrench, socketwrench, or other torquing tool.

A notch locator slot 518 may be formed in the end surface of the hexdrive 517. The notch locator slot 518 preferably comprises a lineargroove machined parallel to the axial notch surface 515a. The notchlocator slot 518 is used as an easy reference to determine the angularorientation of the axial notch surface 515a. To also aid referencing theangular orientation of the axial notch surfaces 515a, paint may beapplied to one half of the drive head end surface.

Unlike the pin assemblies described above with reference to FIGS. 1-9,the pin assemblies of this embodiment have different notch ends 514b.The first pin assembly 512a has a U-shaped notch, designated generallyas reference numeral 515, formed in the notch end 514b of the bar 514.The U-shaped notch 515a is defined by two axial notch surfaces 515a anda radial notch surface 515b. The second pin assembly 512b has a tab 519protruding longitudinally outwardly from the notch end 514b of the bar514. The tab 519 preferably has a rectangular cross section and extendsabout 3/4 inches from the notch end surface 514b. The tab 519 isdesigned to cooperatively engage with the U-shaped notch 515 so that aturning force from one shaft segment 531a can be transmitted to anadjacent shaft segment 531b. The tab is also designed to disengage fromthe U-shaped notch under load when the bars are rotated 90 degrees.

A pair of pin assemblies 512 is shown in FIGS. 18 and 19 in cooperatingengagement with one another to connect during rotation two recessed boltcircle type couplings 531a and 531b. The connection is provided byinserting one pin assembly into each of a pair of aligned, opposedcoupling bolt holes until the tab 519 and the U-shaped notch 515overlap. As the first coupling 531a is rotated, in the direction shownin FIG. 18, the tab from the first pin assembly 512b contacts one of theaxial surfaces 515a of the U-shaped notch 515 of the second pin assembly512b, thereby causing the couplings 531a and 531b to rotate together asa unit. In contrast with the first embodiment described above withreference to FIGS. 1-9, the U-shaped notch 515 and tab 519 connects thecouplings 531 for rotation in either the clockwise or counterclockwisedirection.

A pair of pin assemblies 512 is shown in FIGS. 20 and 21 disengaged fromone another, for example at the end of the rotation phase of a couplingalignment check, on the same two recessed bolt circle type couplings531a shown in FIGS. 18 and 19. The couplings are disconnected byrotating each pin assembly 90 degrees within the bolt holes, therebycausing the previously engaged axial notch surfaces 515a to be separatedby a gap 523 and change their angular orientation relative to thedirection of rotation of the couplings. In FIGS. 20 and 21, thedirection of rotation of the couplings is in the "Z" direction orperpendicular to the plane of the drawing sheet. The disengagement notchgaps 523 result from the fact that the thickness "X" of the tab 519shown in FIG. 21 is less than the distance between axial surfaces 515aof U-notch 515, preferably by 1/8 inches nominal, and because thecoupling bolt holes have bolt hole circle diameters that are nearlyconcentric.

The pin assemblies 512 are rotated by applying a wrench or othertorquing tool to the drive head 517 and simultaneously rotating both pinassemblies 90 degrees. The pin assemblies may be turned either clockwiseor counterclockwise so long as both pins are turned in the samedirection. The pin assemblies 512 can be turned very easily sinceturning resistance is minimal due to the slip fit of the bronze sleeve516 and the bolt hole inner surface which act together like a shaft andbearing.

A seventh embodiment of the coupling pin device of the present inventioncomprises a pair of cooperating pin assemblies 610, 612 as illustratedin FIGS. 22-23. This embodiment is especially useful when one of themating couplings 631b does not have a through hole which traverses theentire width of the coupling as illustrated in FIG. 22. In such a case,the above-described pin assemblies are not practical.

In this embodiment of the invention, the coupling pin device comprises apair of cooperating pin assemblies 610 and 612. The first pin assembly610 has substantially the same construction as the pin assemblydescribed above with respect to FIGS. 1-9. The first pin assembly 610comprises a steel bar 614 and a bronze, brass, or other soft metalsleeve 616 heated and shrunk fit over the annular, axially extendingouter surface of the bar 614 so as to join the bar 614 and sleeve 616together.

The bar 614 has two end surfaces 614b, 614c. A notch is formed in thenotch end 614b of the bar 614. The notch is defined by an axial notchsurface 610a and a radial notch surface 610b.

The axial notch surface 610a is formed, preferably by machining,longitudinally into the bar from the notch end 614b of the bar 164. Theaxial notch surface 610a preferably extends longitudinally about 1 inchnominal, and forms a planar surface parallel to the longitudinal axis ofthe bar 614.

The radial notch surface 610b is formed, preferably by machining,radially into the bar from the outer annular surface of the bar 614 andintersects the axial notch surface 610a, thereby forming the notch. Theradial notch surface extends radially from the axial notch surface 610ato the annular outer surface in a direction transverse, and preferablyperpendicular, to the axial surface 610a and the longitudinal axis ofthe bar 614.

The bar 614 has a drive head 617 formed therein, preferably bymachining, at the drive end 614c so that the bar 614 can be rotated witha standard wrench (not shown). Referring to FIG. 22, the drive head 617is depicted as a hex head in a preferred embodiment, but may be asquare-end head, twelve-point head, or any other geometric shape headwhich facilitates easy turning with a standard wrench, socket wrench, orother torquing tool.

A notch locator slot 618 may be formed in the end surface of the hexdrive 617. The notch locator slot 618 preferably comprises a lineargroove machined parallel to the axial notch surface 610a. The notchlocator slot 618 is used as an easy reference to determine the angularorientation of the axial notch surface 610a. To also aid referencing theangular orientation of the axial notch surface 610a, paint may beapplied to one half of the drive head end surface.

The second pin assembly 612 comprises a bar 650 which is much shorter incomparison to the first bar 614. The second bar 650 has two end surfaces650a, 650b. A notch is formed in the first end surface 650a of the bar650. The notch is defined by an axial notch surface 612a and a radialnotch surface 612b. The notch surfaces have substantially the same shapeand dimensions as the notch surfaces 610a, 610b of the first bar 614.

The annular outer surface of the second bar 650 is short and stayswithin the counterbore 631c of the threaded bore of the second coupling631b. The second bar also has a threaded, longitudinally-extending,through hole 652 which extends from one end surface 650a to the otherend surface 650b. The through hole 652 is used to insert the second bar650 in the counterbored section of the threaded bore of the secondcoupling 631b.

A pair of pin assemblies 612 is shown in FIGS. 22 and 23 in cooperatingengagement with one another to connect during rotation two couplings631a and 631b. The connection is provided by first inserting the secondpin assembly 612 through the bolt hole of the first coupling 631a, andthen inserting the second pin assembly 612 into the bore of the secondcoupling 631b. The second pin assembly is installed using a threaded rod(not shown) which is screwed into the through hole 652 of the second bar650. Next, the first pin assembly 610 is inserted into the bolt hole ofthe first coupling 631a until the axial notch faces 610a, 612a of thebars overlap.

As the first coupling 631a is rotated in the direction shown in FIG. 22,the axial notch face 610a of the first bar 614 contacts the axial notchface 612a of the second bar 650, thereby causing the couplings 631a and631b to rotate together as a unit. The couplings 631 are disconnected byrotating the first pin assembly 90 degrees within the bolt hole, therebycausing the previously engaged axial notch surfaces to be separated by agap and change their angular orientation relative to the direction ofrotation of the couplings.

In the method of the present invention, the coupling pin devicesdescribed above with reference to FIGS. 1-14 and 18-23 are preferablyused during coupling alignment checks. The pin devices temporarilycouple together two adjacent shaft segments during the rotational phaseand quickly uncouple the shaft segments during the measurement phase.

In accordance with this method, the connection bolts connecting a pairof turbine coupling collars are first removed so that the shaft segmentsmay be removed and inspected. After the connection bolts are removed butprior to shaft removal, the turbine shaft alignment at each coupling ismeasured as a reference against which the alignment will be comparedwhen the shaft is reassembled. To conduct a coupling alignment checkusing one of the coupling alignment devices of the present invention,one pin assembly of the coupling alignment device is inserted into eachof a pair of aligned, opposed coupling bolt holes until the axial notchfaces of the pin assemblies overlap. The axial notch faces are orientedsuch that the notch faces contact one another and cause the couplings torotate together as a unit.

After each rotational phase of the coupling alignment check, the pinassemblies are rotated 90 degrees within the bolt holes, thereby causingthe previously engaged axial notch surfaces to be separated by adisengagement gap and change their angular orientation relative to thedirection of rotation of the couplings. The alignment between eachcoupling can then be measured in a stress-free condition. Before thenext rotational phase, the pin assemblies are rotated 90 degrees withinthe bolt holes back to the engaged orientation. This procedure isrepeated until the predetermined number of alignment measurements hasbeen achieved.

In the method in accordance with another embodiment of the invention,the coupling pin device described above with reference to FIGS. 17-19,is preferably used to correct coupling collar concentricity or "couplingrunout". The above-described coupling runout eliminator (CRE) pindevices can be used to precisely adjust the concentric alignment of, forexample, the turbine end (TE) and the generator end (GE) coupling halvesto each other during initial coupling assembly or reassembly in order toeliminate differential coupling runout (DCR). The method according tothis embodiment of the invention is described with reference to FIGS.24-26. The DCR between the TE coupling and GE coupling is illustrated inexaggerated proportion in FIG. 24 wherein reference numeral 431adesignates the TE coupling and reference numeral 431b represents the GEcoupling half. In FIG. 24, the center of the TE coupling is designatedby reference numeral 432a while the center of the GE coupling isdesignated by reference numeral 432b.

To correct DCR using the method of the present invention, the TE and GErotor coupling collars are initially lined up for assembly using matchedmarkings provided on the couplings. Four (4) temporary bolts areinstalled in equally spaced hole locations such as at the holesdesignated by reference numeral 20a. Preferably, the temporary bolts arepermanent hydraulic bolts without sleeves so that the bolts have a 1/32inch clearance (minimum) in the holes. The temporary bolts are tightenedsufficiently to draw the couplings close together but not so tight thatthe coupling faces are securely clamped together.

Aligned clock position between the mating coupling bolt holes is thenestablished by installing two CRE pin devices in adjacent holes such as,for example, holes 20b in FIGS. 24 and 25. The axial notch faces 415aare oriented as shown in FIG. 25 such that the length of the notchcorner 414d is parallel to a radial line extending from the center 432aof the TE coupling 431a through the center of the bolt hole 20b. Alignedclock position between mating coupling holes is achieved by rotating theadjustment bolts 422 either clockwise or counterclockwise to wedge orscissor the couplings relative to one another. The rotor attached to thecoupling is rotating a slight amount in order to accommodate scissoringmovement.

After aligned clock position is achieved between the mating couplingbolt holes 20, the temporary bolts are tightened enough to close up thegap between the TE and GE couplings and to hold the couplings firmlytogether during rotation. When all 4 temporary bolts are tightened, thetwo CRE pin assemblies are removed.

A second method of aligning clock position is to use normal bolting,either hydraulic or body bound bolts, to draw up and hold the couplingsfirmly together. These tight fitting bolts must be removed prior toadjusting the concentricity with the pin assemblies.

An initial DCR check is performed by rotating the shaft and taking analignment (runout) reading every 45 degrees. The location of maximumpositive differential coupling runout (DCR) of the TE coupling withrespect to the GE coupling is marked with an appropriate indicator suchas the letter "H". This angular location is hereinafter referred to asthe H-position.

The shaft segments are then rotated such that the H-position is located45 degrees clockwise from top dead center as shown in FIG. 26. Theamount of differential runout which exists at the H-position, 135, 225,and 315 degree positions is measured and recorded. A positive value isassigned to the DCR value when the runout of the GE coupling is greaterthan the runout of the TE coupling. A negative value is assigned to theDCR value when the runout of the GE coupling is less than the runout ofthe TE coupling. At this point, if the coupling spacer is notconcentric, install spacer alignment brackets (SAB) 90 degrees apartaround the circumference of the coupling to correct the alignment of thespacer. Set up four (4) separate mag base dial indicators to assist.

Next, install four (4) CRE pin assemblies 412 at 45, 135, 225, and 315degrees from top dead center as shown in FIG. 26. Orient the CRE pinassemblies 412 such that the length of the notch corner 414d isperpendicular to a radial line extending from the center 432a of the TEcoupling 431a through the center of the bolt hole 20. Further, theadjustment bolts 422 should be located in between the center 432a of thecoupling 431a and the axial notch surface 415a. Hand tighten the CRE pinassemblies so that the axial wedge surfaces of the pins make contact.

Set up four (4) separate mag base dial indicators at the 45, 135, 225,and 315 degree locations. The mag base should preferably be on the TEcoupling while the dial button should preferably be on the GE coupling.Set each indicator to 1/2 of the value of DCR recorded for thoselocations.

Loosen the temporary bolts enough so that the couplings may be jacked orscissored relative to one another. Adjust the CRE pin assemblies untilthe runout of the couplings is eliminated. Starting at the H-position,rotate the adjustment bolt 422 on that CRE pin assembly until theH-position adjacent that indicator reads zero. Adjust the other threeCRE pin assemblies until their adjacent indicators read zero. If, atthis point, spacer runout correction is also needed, then slightlyloosen the spacer attachment bolts and adjust spacer using the SABs anddial indicators. Re-tighten the four (4) temporary bolts to clamp thecouplings firmly together. Monitor the CRE dial indicators during thetightening process. Verify that the indicators still read zero. Ifnecessary, adjust the CRE pin assemblies as needed to maintain couplingsin the desired axially aligned position during the tightening process.Repeat DCR check by rotating shafting and taking an alignment (runout)reading every 45 degrees.

At this point, the couplings are concentric and may be line bored.Install four (4) permanent bolts with hydraulic sleeves or fitted bolts(non-hydraulic) on the couplings and then remove the CRE pin assemblies.The CRE pin assemblies may be removed by pulling them out withall-thread and strongback. Pulling is performed in a conventional mannerfor pulling a dowel.

What is claimed is:
 1. A tool for aligning multiple shaft segments whichare coupled together to form a single rotating shaft, said shaftsegments having couplings with a plurality of radially-located boltholes extending there through, said tool comprising an elongatecylindrical bar having:a) an annular, axially-extending outer surface;b) rotating means on a first end of said bar; c) engaging/disengagingmeans fixed on a second end of said bar; said bar constructed andarranged to be temporarily inserted through a bolt hole in the collar ofthe first shaft and partially through an aligned hole in an adjacentcoupling of the second shaft, until at least a portion of saidengaging/disengaging means is positioned within the bolt hole of thesecond collar, said engaging/disengaging means constructed and arrangedto engage the second collar so that a turning force from the first shaftis transmitted to the second shaft, and constructed and arranged todisengage from the second collar by rotating said bar after rotation ofthe shafts is ceased.
 2. The tool recited in claim 1, saidengaging/disengaging means comprising an extension formed on the secondend of said bar, said extension having an axially-extending surface anda radially-extending surface at the second end of said bar, saidradially-extending surface extending a distance d1 in a first radialdirection and extending a distance d2 in a second radial directionperpendicular to the first radial direction, wherein d1 is greater thand2.
 3. The tool recited in claim 1, said bar constructed and arranged todisengage from the second collar when the bar is rotated 90° from anengaged position.
 4. The tool recited in claim 1, said rotating meanscomprising a lug fixed to the first end of the bar, said lug havingmultiple flat surfaces which are constructed and arranged to receive awrench or socket for applying a turning force.
 5. The tool recited inclaim 1, said rotating means comprising a female socket formed in thefirst end of said bar, said socket constructed and arranged to receive amale torquing tool.
 6. The tool recited in claim 1, said bar includingan indicator on said rotating means for indicating the angularorientation of said engaging/disengaging means.
 7. The tool recited inclaim 1, said bar including a sleeve on the annular, axially-extendingouter surface, said sleeve being shorter than the axial distance betweensaid rotating means and said engaging/disengaging means.
 8. Method ofaligning multiple shaft segments which are coupled together to form asingle rotating shaft, said shaft segments having couplings with aplurality of bolt holes extending there through, comprising the stepsof:a) providing an alignment tool comprising an elongate cylindrical barhaving:i) an annular axially-extending outer surface; ii) rotating meanson a first end of said bar; and, iii) engaging/disengaging means on asecond end of said bar; b) inserting the tool through a bolt hole in thecollar of a first shaft and partially through an aligned bolt hole in anadjacent coupling of a second shaft until at least a portion of saidengaging/disengaging means is positioned within the hole of the secondcollar; c) temporarily connecting the couplings by engaging the bar withthe collar of the second shaft so that the couplings rotate together asa unit; d) rotating the shaft segments; e) ceasing rotation of the shaftsegments; f) disconnecting the couplings by disengaging the bar from thecollar of the second shaft by rotating the cylindrical bar within thebolt holes; and, g) measuring the coupling alignment of the adjacentshaft segments.
 9. The method recited in claim 8, wherein said bar isdisengaged by rotating the bar 90° within the bolt holes.
 10. The methodrecited in claim 8, wherein said cylindrical bar is rotated by atorquing tool applied to said rotating means.